Composition and method for forming a weld-surfaced alloyed steel layer of steel

ABSTRACT

This invention relates to articles having a wearing surface affixed thereto by means of welding. The invention is particularly applicable to workpieces and tools, such as machine knives. In particular, the invention discloses novel compositions and methods for cladding or surfacing a metal article by means of a so-called band or flat strip electrode thereby producing a very hard wearing layer of allowed steel on said article. The use of flat strip electrodes results in a flat and uniform penetration and, consequently, in a slight and uniform mixing with the base material of the article.

United States Patent [191 Plilckinger et al.

[ COMPOSITION AND METHOD FOR FORMING A WELD-SURFACED ALLOYED STEEL LAYEROF STEEL [75] Inventors: Erwin Pliickinger; Hermann Ornig; AlfredSchmidt, all of Kapfenberg, Austria [73] Assignee: Gebruder Bohler & C0.Aktiengesellschaft, Kapfenberg, Austria [22] Filed: June 21, 1968 [21]Appl. No.: 744,603

Related US. Application Data [63] Continuation-impart of Ser. No.580,157, Sept. 15, 1966, which is a continuation-in-part of Ser. No.490,789, Septh28, 1965, abandoned.

[30] Foreign Application Priority Data Sept. 17, 1965 Austria ..A8490/65 Sept. 17, 1965 Austria ..A 8491/65 [56] References Cited UNITEDSTATES PATENTS 2/1939 Emmons ..75/126 March 6, 1973 2,575,219 11/1951Giles ..75/126 2,863,981 12/1958 Thomas ..75/126 3,078,363 2/1963Johnson 260/525 3,102,025 8/1963 Wilcox ..75/128 3,139,508 6/1964Freeman ..219/74 3,195,230 7/1965 Peck ..29/496 3,177,339 4/1965 Sheruhn..1 19/5 1 .11

3,223,818 12/1965 Chyle ..219/73 3,493,713 2/1970 Johnson ..219/762,206,375 7/ 1940 Swift ..29/491 2,948,805 8/1960 Berg ..219/1463,035,934 5/1962 Cape ..75/171 3,118,760 1/1964 Avery ..75/128 A3,271,553 9/1966 Johnson ..219/76 Primary Examiner-I-lyland BizotAtt0rney-Arthur O. Klein [5 7 ABSTRACT This invention relates toarticles having a wearing surface affixed thereto by means of welding.The invention is particularly applicable to workpieces and tools, suchas machine knives.

In particular, the invention discloses novel compositions and methodsfor cladding or surfacing a metal article by means of a so-called bandor flat strip electrode thereby producing a very hard wearing layer ofallowed steel on said article. The use of flat strip electrodes resultsin a flat and uniform penetration and, consequently, in a slight anduniform mixing with the base material of the article.

4 Claims, 2 Drawing Figures COMPOSITION AND METHOD FOR FORMING AWELD-SURFACED ALLOYED STEEL LAYER OF STEEL CROSS REFERENCE TO RELATEDAPPLICATION This is a continuation-in-part application of our copendingapplication Ser. No. 580,157, filed on Sept. 15, 1966.

The application Ser. No. 580,157 is a continuationin-part of ourapplication Ser. No. 490,789, filed on Sept. 28, I965, now abandoned.

BACKGROUND OF THE INVENTION It is known to regenerate worn and spentportions of tools by weld-surfacing. For example, worn teeth ofexcavators are regenerated by weld-surfacing, using welding rods of hardmanganese steels. Great difficulties have been encountered in producingweld-surfaced wearing layers with ordinary round welding rods, havinghigh speed steel compositions. (Welding with such electrodes causes adeep penetration of the base material. Therefore the welding compositionof the first layer consists of about 50 percent of the base materialwhich is generally composed of mild steel.) This penetration results inreducing the percentage of important alloying elements in the wearinglayer. In order to compensate for this reduction, the wearing surface isgenerally produced by two or more layers. Because such a proceduregenerally produces hot cracking, the base layer has to be reheated up to300C. Preheating causes low hardness and therefore a hardening processafterwards has to be applied. The hardening process results in adistortion of the workpiece and a big grain size in the base metal.

It is furthermore known to use flat strip electrodes of copper, mildsteel and stainless steel for s'urface welding. The use of high-speedsteel flat strip electrodes used for surface welding does not, however,form part of the prior art. It has been surprisingly found that, whenusing a flat strip or band electrode of high speed steel underpredetermined conditions, some of which are defined by certain rangesset forth in the claims, weld-surfaced wearing layers can be produced onbase layers, which result in composite articles of superior mechanicaland physical properties. For example, such a composite article has adifferent, more uniform and, consequently, much better microstructure.Consequently, workpieces and tools of distinctly superior quality can beproduced with the methods for producing composite articles and thecomposite articles disclosed herein.

The use of conventional filler rods or welding wires resulted in asurface which was not smooth and required subsequent machining in manycases. The machining of surfaces consisting of high-speed alloyed steelsis, however, very difficult and expensive.

Another disadvantage lies in the frequent formation of contractioncracks in the weld-surfaced layers produced with conventional fillerrods or welding wires. This phenomenon can be explained as follows: Dueto their relatively deep penetration, the cross-section of the weld beadis approximately circular. During solidification the preferreddirections of the crystal axes are approximately at right angles to thewelded surface. The impurities in the weld are one of the main causesfor a formation of contraction cracks and are favored in that portion ofthe weld which solidifies last, i.e., the interior of the bead. Thus,contraction cracks frequently form in the interior of the beads. Inusing a flat strip electrode the bead is flat and solidificationproceeds from base metal to the surface of the bead. Thus, theimpurities are enriched at the surface of the bead and, consequently,the possibility for causing contraction cracks is diminished.

SUMMARY OF THE INVENTION It is accordingly a primary object of thepresent invention to provide a method of producing a wearing surfaceconsisting of wear resisting alloyed steel such as high speed steel,high chromium steel, high manganese steel of other wear resisting alloyse.g., of the cobalt type on a base layer of tough steel particularly forworkpieces or tools by means of a flat strip electrode consisting ofsaid high speed alloyed steel.

It is another primary object of this invention to provide a compositearticle particularly adapted for use in workpieces and tools which has abase of tough steel and a weld-surfaced wearing layer consisting of wearresisting alloyed steel such as high speed steel, high chromium steel,high manganese steel or other wear resisting alloys e.g., of the cobalttype welded thereon by means of a flat strip electrode.

It is another more specific object of the present invention to provide amethod for producing a wearing surface consisting of high speed alloyedsteel by means of a flat strip electrode consisting of the same materialon a base of tough steel, wherein said flat strip electrode uniformlypenetrates the base and, consequently, is mixed only slightly with thebase material.

In the preferred weld surfacing practice of the present invention, abare electrode, of the aforedescribed compositions, in the form of arelatively thin strip of metal is fed to the welding zone. A weldingcurrent is caused to flow through a circuit which includes the work endof the strip. When using a flat strip electrode, the arc travels backand forth across the strip, maintaining its juncture with the work atthe point of least resistance. Accordingly, the heat produced by the arcencompasses a greater width in its path of travel across the work and,consequently, the penetration and resultant dilution are kept at a mnimum.

While preferably the submerged arc welding technique is to be used withthe subject invention, it is not limited to this technique as otherwelding techniques could be adapted to the method of the presentinvention.

BRIEF DESCRIPTION OF THE DRAWING The invention is illustrated by way ofexample in the accompanying drawing which forms part of the applicationand in which a machine knife embodying the invention is shown in FIG. 1in a perspective view, and in FIG. 2 in a fragmentary sectional viewtaken through the weld-surfaced layer.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to the drawing,the machine knife comprises a base 1, which is provided with aweld-surfaced layer 2 forming a working surface or cutting edge portionof the knife. The base 1 has exposed non-working surface portions 3.

FIG. 2 shows the uniform, relatively small penetration of theweld-surfaced layer 2 into the base 1.

Welds of good surface appearance were deposited by using a flat stripelectrode over a fairly wide range of welding conditions which will beset forth below. Cross sectional examination indicated that with theproper combination of conditions a relatively low order of dilution anduniform penetration of the weld-surfaced layer resulted withoutrequiring preheating of the base. When welding conditions outside theranges set forth below were used the resulting weld-surfaced layerproved unsatisfactory. A microstructural examination was used todetermine the quality of the weld-surfaced layer. Only when weldingconditions within the ranges One of the more important advantagesfeatures of the present invention lies in the fact that the baserequires no preheating. In some cases it has proven advantageous toplace the base on a copper plate in order to speed up the coolingprocess. In some cases the composite article is heat treated after thewelding and the removal of the slag has been completed. However, itshould be noted that this additional step serves only to obtain afurther hardening of the weld-surfaced layer due to the well knownprecipitation and segregation effect and really does not pertain to thegist of the present invention.

5. Speed of welding with a flat strip electrode It has been found thatthe most advantageous results would be obtained when using a travelspeed of 7 cm to 30 cm per minute.

6. Composition of the flat strip welding electrode The chemicalcomposition of the band electrode depends on the purposes for which thetools according to the invention are used. There follows hereafter atabu- Iation.

orffifirciiL coMrosl'rioN (FETANVD ELECTRODES Percent Type of alloy C SiMn Cr Mo Ni V W Go Nb Fe Cu 1. High speed steels 0.2-1. 7 0.1-1. 70.1-2.0 1.0-7.0 0.1-12.0 Rest 0.0-0.4 2. High chromium steels.. 0. 1-1.1 0. 2-4. 0.3-0.8 12. 0-21. 0 0 0-3 0 Rest 3. High manganese steels1.0-1.5 0.3-0.6 6.0-18.0 0.1-2.0 0 1-2 0 Rest 4. Stellites 0. 0-1. 2 0.-1. 0 0. 1-1. 0 25. 0 0.0-5

set forth below were used was the required chemistry found, togetherwith satisfactory hardness and a microstructure providing the basis forgood cutting properties. The amount of base metal dilution did notexceed of the cutting edge material that had been built up on thisknife, no further layers of weld metal being necessary. Anothersignificant fact is that the orientation of most of the individualgrains making up the solidified structure are substantially oriented ina direction perpendicular to that of the stresses when the workpiece isin operation. It is obvious that the angular orientation of the crystalsin a weld-surfaced layer influences the adhesiveness of the layer and,consequently, the likelihood of cracking under stress.

The ranges of welding conditions which proved satisfactory while using asubmerged arc welding technique are as follows:

1. Dimensions of the flat strip or band electrode It has been found thatflat strip electrodes having a width ranging from 5 mm to 120 mm and athickness ranging from 0.3 mm to 3.2 mm proved satisfactory, whereas theuse of a flat strip electrode having one or more dimensions fallingoutside these ranges proved to be unsatisfactory.

2. Current used in welding with a flat strip electrode It has been foundthat the most advantageous results would be obtained when using awelding current density ranging from 10 to 50 amperes per mm. Highercurrent densities resulted in too great penetration, lower currents in apoor appearance of the welding bead.

3. Voltage used in welding with a flat strip electrode It has been foundthat the most advantageous results would be obtained when using awelding voltage ranging from 22 volts to 40 volts. Lower voltages causedan increase in penetration, higher voltages caused too violent arcing.

4. Rate of cooling when welding with a flat strip electrode Flux SiO,Al,0 FeO MgO CaO MnO Cal,

Linde UM 8 36 13 1.5 9 28 8 3 Linde UM 50 41 4 1.5 I0 39 4 Linde UM 2050 4 0.5 10 29 6 Lincoln 36 14 3.0 27 l3 6 Flux 840 In some cases it isnecessary to mix these fluxes with up to 10 percent carbon to get ahigher carbon content in the weld metal.

BASE MATERIAL USED WITH THE FLAT STRIP ELECTRODE The flat stripelectrode of the present invention may be used with a large number ofdifferent types of metallic base materials. A base of tough steel isfrequently used because it frequently constitutes the base material inworkpieces, the working surfaces of which are to be regenerated byweld-surfacing. Consequently, the following compositions of basematerials are given by way of examples only and the invention is not tobe limited in this respect.

a. a low alloyed or non alloyed steel having 0.05 to 0.65% C; 0.05 to0.5 Si; 0.4 to 2.0% Mn; 0.0 to 2.5% Cr; 0.0 to 1.0% M; 0.0 to 2.0% Ni;0.0 to 0.3% V.

b. a stainless steel of the type 18 Cr 8 Ni with max.

0.1 c; max. 2.5% Si; max. 2.5 Mn; 16 m 28% Cr; 7 to 22% Ni; 0.0 to 5.0%M0; 0.0 to 4.0% Cu; 0.0 to 1.5% Nb; 0.0 to 1% Ti; 0.0 to 2.0% A1.

The invention will be explained more fully by the following examples, itbeing understood, however, that these examples are given by way ofillustration and not by way of limitation and that many changes may beeffected without affecting the scope and spirit of the invention asdefined in the appended claims.

Example 1 To make a machine knife a base member of non-a1- loyed steelwas used as a base material which had the following composition:

C Si Mn S P the remainder Fe with the usual impurities.

The base member had the following dimensions 60 mm X mm X 3000 mm. Alonga longitudinal edge of 30 the base member a groove having across-section of mm X 4 mm was formed. The base member was tightlyclamped to a copper base plate. A flat strip electrode having across-section of 18 mm X 1.8 mm was used to surface-weld a wearing layer2 in the base member 1. The flat strip electrode had the followingcomposition:

C Si Mn Cr W Mo V the rest iron with the usual impurities.

A well known commercial flux granular material UM 50 was used withoutpreheating the base member and in this way the groove was filled withwelded material from the flat strip electrode.

An analysisof the finished composite article indicated the followingcomposition for. the weld-surfaced layer:

C Si Mn Cr W Mo V the rest iron with the usual impurities.

The welding conditions were as follows:

Current 950 A (=29A/m voltage 28 V; travel speed 13 cm/min. After theslag was removed the blank was tempered at 540C. and thereby the knifewas hardened to 61 RC. The blank was then finished and sharpened bygrinding.

Example 2 Manufacturing another type of machine knife The base memberwas dimensioned 79 X 19 X 3000 mm and had a longitudinal groove alongone edge having a cross-section of 4 X mm and the following composition:

C Si Mn the rest iron with the usual impurities.

The submerged arc welding technique was used with a UM-SO granular fluxmaterial. The base member was clamped to a copper base plate. The bandor flat strip electrode used had a cross-section of 23 X 1.6 mm whichhad the following composition:

C Si Mn Cr W Mo V the remainder iron with the usual impurities.

The resultant weld-surfaced wearing layer had the following composition:

C Si Mn Cr W Mo V the remainder iron with the usual impurities.

The welding conditions were as follows: Current 650 amperes; voltage 25volts, travel speed 20 cm/minute.

Example 3 Work on a chopping knife for chopping wood.

C Si Mn Cr W V base member %0.45 0.2 0.6

flat strip electrode %0.75 0.2 0.3 4.3 18 1.1 weld-surfaced wearinglayer %0.51 0.6 0.7 3.5 15.2 0.6

the remainder Fe with the usual impurities Example 4 Producing achopping knife or axe for the wood industry The base member wasdimensioned 200 X 20 X 600 mm and had a groove along one of its edgeshaving a cross-section of 35 X 4 mm. The submerged arc welding techniquewas used with a UM-SO granular flux material without preheating the basematerial. The base member was clamped to a copper base plate.

The welding conditions were as follows: Current 1150 amperes (25amperes/mm); voltage 35 volts; travel speed cm per minute. Thecross-section of the flat strip electrode measured 33 X 2.3 mm.

An analysis indicated the following:

A circular cutting knife The base member was a disc having a diameter of550 mm. and a thickness of 50 mm. It has grooves on both sides of itsedges with a cross-section of 18 X 5 mm. each. The grooves were filledup by means of the submerged arc welding technique with a flat stripelectrode having a size of 20 X 1.5 mm. using a UM-SO granular fluxmaterial without preheating.

The welding conditions were as follows: Current 720 amperes (24 amperesper mm); voltage 30 volts; travel speed 30 cm per minute.

An analysis indicated the following:

C Si Mn Cr W Mo V base member 3120.25 0.25 0.4 1 0 0.3 flat stripelectrode %0.85 0.30 0.35 4 3 6.1 5.1 2.0 weld-surfaced %O.52 0.60 0.9 30 5.0 4.2 1.3

wearing layer the remainder iron with the usual impurities.

Example 6 Another type of circular cutting knife The base memberconsisted of a round disc having a diameter of 400 mm and a thickness of20 mm. The circumferential face of the disc is weld surfaced with aUM-50 granular flux material without being preheated forming a layer of20 X 4 mm.

The welding conditions were as follows: Current 720 amperes (24 amperesper mm); voltage 30 volts; travel speed 30 cm per minute. Thecross-section of the flat strip electrode measured 20 X 1.5 mm.

An analysis indicated the following:

C Si Mn Cr W Mo Ni Co V base member 1110.30 0.3 0.5 2.0 0.3 2.0 flatstrip electrode 111.05 0.2 0.3 3.7 1.5 9.5 8.0 1.5 weld-surfaced 110.730.6 0.7 3.2 0.8 8.5 0.1 7.2 1.1

wearing layer the remainder Fe with the usual impurities.

Example 7 A machine knife for the paper industry The base member wasdimensioned 210 X 18 X 1500 mm and had a groove along one of itslongitudinal edges having a cross-section of 38 X 5 mm. The submergedare welding technique was used with a UM-S0 granular flux materialwithout preheating the base member.

The welding conditions were as follows: Current 1350 amperes (=14amperes/mm voltage 36 volts; travel speed 22 cm/min. The cross-sectionof the flat strip electrode measured 38 X 2.5 mm.

An analysis indicated the following:

C Si Mn Cr W Mo V base member 36060 0.3 0 6 flat strip electrode %1.700.3 03 12.0 0.5 0.6 0.1 weld-surfaced 961.20 0.8 0 3 8.2 0.3 0.4 0.05

wearing layer the remainder Fe with the usual impurities.

Example 8 A circular cutting knife The base member consisted of a rounddisc having a diameter of 300 mm and a thickness of 15 mm with anannular groove along its outer peripheral edge having a cross-sectionmeasuring 15 X 3 mm. The submerged are welding technique was used with aUM-50 granular flux material without preheating the base member.

The welding conditions were as follows: Current 600 amperes (40 amperesper mm); voltage 26 volts; peripheral travel speed 30 cm per minute. Thecross section of the flat strip electrode measured 15 X 1.0

An analysis indicated the following:

C Si Mn Cr W Mo V base member %0.48 0.3 1.8 flat strip electrode %0.550.85 0.3 8.5 l l 1.2 0.13 weld-surfaced 950.51 1.1 0.5 7.0 09 1.0 0.1

wearing layer the remainder Fe with the usual impurities.

Example 9 Wood fiber planing knife The base member was dimensioned 8 X X200 mm and had a groove along one of its edges having a cross-section of20 X 3 mm. The submerged arc welding technique was used with a UM-20granular flux material without preheating the base member.

The welding conditions were as follows: Current 700 amperes; voltage 27volts; travel speed 26 cm per minute. The cross-section of the flatstrip electrode measured 20 X 1.5 mm.

An analysis indicated the following:

C Si Mn Cr W base member 96025 0.2 0.4 s flat strip electrode %0.76 0.50.5 2.5 3.3 weld-surfaced %0.53 0.9 0.3 1.7 2.5

wearing layer the remainder Fe with the usual impurities Example 10Another type of wood fiber planing knife The base member was dimensionedX 100 X 6000 mmm and had a groove along one of its edges having across-section of 15 X 5 mm. The submerged are welding technique was usedwith a Lincoln Flux 840 granular material without preheating the basemember.

The welding conditions were as follows: Current 530 amperes; voltage 25volts; travel speed 23 cm per minute. The cross-section of the flatstrip electrode measured 15 X 1 mm.

An analysis indicated the following:

C Si Mn CrMo Ni Cu base member 3120.35 0.25 0.45 s flat strip electrode%0.60 0.20 0.20 1.7 0.2 4.5 0.4 weld-surfaced %0.42 0.50 0.50 1.3 0.24.0 0.3

wearing layer the remainder Fe with the usual impurities.

Example 1 1 Dredger bucket The base member was dimensioned 15 X 100 X6000 mm. Strips consisting of hard manganese steel and having 40 mmwidth and thickness were welded on both sides (exterior and interior).The submerged are welding technique was used with a UM-50 granular fluxmaterial without preheating the base member.

The welding conditions were as follows: Current 600 amperes; voltage 3.1volts; travel speed 15 cm per minute. The cross-section of the flatstrip electrode measured 40 X 1.0 mm.

An analysis indicated the following:

C Si Mn base membe 950.26 0.5 0.8 flat stn'p electrode %1.2 0.2 13.5weld-surfaced 960.8 0.6 9.2

wearing layer the rest iron with the usual impurities.

Example 12 Pressure bar, for wood-peeling machine The base member wasdimensioned 60 X 15 X 3500 mm and had a groove along one of its edgeshaving a cross-section of 15 X 5 mm. The submerged arc welding techniquewas used with a UM-80 granular flux material without preheating the basemember.

The weldingconditions were as follows: Current 500 amperes; voltage 27volts; travel speed 18 cm per minute. The cross-section of the flatstrip electrode measured 14 X 1.0 mm.

An analysis indicated the following:

C Si Mn Cr W Mo Co Fe base member 1120.15 0.25 0.6 0.3 rest flat stripelectrode 760.40 0.3 0.3 29.5 5.7 rest 3 weld-surfaced 160.35 0.5 0.725.1 4.5 rest 14 wearing layer Example 13 Cotton shearing knife The basemember was dimensioned 40 X 6 X 200 mm and had a longitudinal groovealong one of its edges having a cross-section of 12 X 3 mm.

The submerged arc welding technique was used with a UM-SO granular fluxmaterial without preheating the base member.

The welding conditions were as follows: Current 350 amperes; voltage 22volts; travel speed 23 cm per minute. The cross-section of the flatstrip electrode measured 12 X 1.0 mm.

An analysis indicated the following:

The base member was dimensioned 250 X 150 X 1200 mm and wasweld-surfaced with a layer measuring 120 X 10 X 1000 mm by means of thesubmerged are welding technique while using a the base. 20 granu larflux material without preheating the base The welding conditions were asfollows: Current 4000 amperes; voltage 40 volts; travel speed 10 cm perminute. The cross-section of the flat strip electrode measured 120 X 2.8mm.

An analysis indicated the following:

C Si Mn Cr Mo Fe base member %0.25 0.5 0.8 Rest flat strip electrode9110.40 0.3 1.0 19 2.5 Rest weld-surfaced %0.30 1.3 0.4 14 2.0 Restwearing layer Example 15 An armored valve cone member The periphery ofthe valve member of the valve cone blank was weld-surfaced by means ofthe submerged arc welding technique using a UM- granular fluxmaterialwithout preheating the base.

The welding conditions were as follows: Current 280 amperes; voltage 22volts; travel speed 19 cm per minute. The cross-section of the flatstrip electrode measured X 0.8 mm.

An analysis indicated the following:

C Si Mn Cr Ni W Fe Co Base member% 0.43 2.5 1.0 18.5 9.5 1.0 Rest Flatstrip electrode 0.32 0.8 1.8 28.0 1.3 4.5 1.0 Rest Weld-surfaced wearinglayer% 0.28 1.3 2.3 24.6 1.5 3.9 6.5 Rest There will now be obvious tothose skilled in the art many modifications of the above embodiments.Such modifications will come within the scope of the invention ifdefined by the following claims.

What is claimed is:

1. A process for producing a composite article having a base of toughsteel, said article having non-working surfaces and working surfaces,comprising the steps of submerged arc weld-surfacing said workingsurfaces by means of a flat strip electrode having a width in the rangeof 5 mm to 120 mm and a thickness in the range of 0.3 mm to 3.2 mm; saidflat strip electrode consists of the following composition: 2.0 to 1.7percent carbon, 0.1 to 1.7 percent silicon, 0.3 to 2.0 percentmanganese, 1.0 to 7.0 percent chromium, 0.1 to 12 percent molybdenum,0.1 to

5.0 percent nickel, 0.1 to 6 percent vanadium, 0.5 to percent cobalt,0.5 to 0.4 percent copper, 0.2 to 0.3 percent nobium, balance iron withthe usual impurities; said flat strip electrode used for weld-surfacingsaid working surfaces travels at a speed in the range of 7-30 cm perminute; the current density used in said-submerged arc welding techniqueranges from 10 to 50 amperes per mm; and

the voltage used in said submerged arc welding technique ranges from 2240 volts. 2. A process for producing a composite article having a baseof tough steel, said article having non-working surfaces and workingsurfaces, comprising the steps of submerged arc weld-surfacing saidworking surfaces by means of a flat strip electrode having a width inthe range of 5 mm to 120 mm and a thickness in the range of 0.3 mm to3.2 mm;

said flat strip electrode consists of the following composition: 0.1 1.1percent carbon, 0.2 4.0 percent silicon, 0.3-0.8 percent manganese,12.0-21.0 percent chromium, 0.0-3.0 percent molybdenum, 0.1-2.0 percentnickel, 0.0-0.3 percent vanadium, balance iron with the usualimpurities;

said flat strip electrode used for weld-surfacing said working surfacestravels at a speed in the range of 7-30 cm per minute;

the current density used in said submerged arc welding technique rangesfrom 10 to 50 amperes per mm; and

the voltage used in said submerged arc welding technique ranges from 2240 volts. 3. A process for producing a composite article having a baseof tough steel, said article having non-working surfaces and workingsurfaces, comprising the steps of submerged arc weld-surfacing saidworking surfaces by means of a flat strip electrode having a width inthe range of 5 mm to mm and a thickness in the range of0.3 mm to 3.2 mm;

said flat strip electrode consists of the following composition:l.0-l.5percent carbon, 0.3-0.6 percent silicon, 60-180 percent manganese,0.1-2.0 percent chromium, 0.1-2.0 percent molybdenum, 0.1-6.0 percentnickel, balance iron with the usual impurities; said flat stripelectrode used for weld-surfacing said working surfaces travels at aspeed in the range of 7 30 cm per minute;

the current density used in said submerged arc welding technique rangesfrom 10 to 50 amperes per mm; and

the voltage used in said submerged arc welding technique ranges from 2240 volts. 4. A process for producing a composite article having a baseof tough steel, said article having non-working surfaces and workingsurfaces, comprising the steps of submerged arc weld-surfacing saidworking surfaces by means of a flat strip electrode having a width inthe range of 5 mm to 120 mm and a thickness in the range of0.3 mm to 3.2mm;

said flat strip electrode consists of the following composition:0.01.2percent carbon, 0.5-1.0 percent silicon, 0.1-1.0 percent manganese,25.0-37.0 percent chromium, 0.1-7.0 percent nickel, 2.0-25.0 percenttungsten, 0.0 5 percent iron, balance cobalt with the usual impurities;

said flat strip electrode used for weld-surfacing said working surfacestravels at a speed in the range of 7 30 cm per minute; the currentdensity used in said submerged arc welding technique ranges from 10 to50 amperes per mm, and I the voltage used in said submerged arc weldingtechnique ranges from 22 40 volts.

I 8 i 0 i

1. A process for producing a composite article having a base of toughsteel, said article having non-working surfaces and working surfaces,comprising the steps of submerged arc weld-surfacing said workingsurfaces by means of a flat strip electrode having a width in the rangeof 5 mm to 120 mm and a thickness in the range of 0.3 mm to 3.2 mm; saidflat strip electrode consists of the following composition: 2.0 to 1.7percent carbon, 0.1 to 1.7 percent silicon, 0.3 to 2.0 percentmanganese, 1.0 to 7.0 percent chromium, 0.1 to 12 percent molybdenum,0.1 to 5.0 percent nickel, 0.1 to 6 percent vanadium, 0.5 to 10 percentcobalt, 0.5 to 0.4 percent copper, 0.2 to 0.3 percent nobium, balanceiron with the usual impurities; said flat strip electrode used forweld-surfacing said working surfaces travels at a speed in the range of7-30 cm per minute; the current density used in said submerged arcwelding technique ranges from 10 to 50 amperes per mm; and the voltageused in said submerged arc welding technique ranges from 22 - 40 volts.2. A process for producing a composite article having a base of toughsteel, said article having non-working surfaces and working surfaces,comprising the steps of submerged arc weld-surfacing said workingsurfaces by means of a flat strip electrode having a width in the rangeof 5 mm to 120 mm and a thickness in the range of 0.3 mm to 3.2 mm; saidflat strip electrode consists of the following composition: 0.1 - 1.1percent carbon, 0.2 - 4.0 percent silicon, 0.3-0.8 percent manganese,12.0-21.0 percent chromium, 0.0-3.0 percent molybdenum, 0.1-2.0 percentnickel, 0.0-0.3 percent vanadium, balance iron with the usualimpurities; said flat strip electrode used for weld-surfacing saidworking surfaces travels at a speed in the range of 7-30 cm per minute;the current density used in said submerged arc welding technique rangesfrom 10 to 50 amperes per mm; and the voltage used in said submerged arcwelding technique ranges from 22 - 40 volts.
 3. A process for producinga composite article having a base of tough steel, said article havingnon-working surfaces and working surfaces, comprising the steps ofsubmerged arc weld-surfacing said working surfaces by means of a flatstrip electrode having a width in the range of 5 mm to 120 mm and athickness in the range of 0.3 mm to 3.2 mm; said flat strip electrodeconsists of the following composition: 1.0-1.5 percent carbon, 0.3-0.6percent silicon, 6.0-18.0 percent manganese, 0.1-2.0 percent chromium,0.1-2.0 percent molybdenum, 0.1-6.0 percent nickel, balance iron withthe usual impurities; said flat strip electrode used for weld-surfacingsaid working surfaces travels at a speed in the range of 7 - 30 cm perminute; the current density used in said submerged arc welding techniqueranges from 10 to 50 amperes per mm; and the voltage used in saidsubmerged arc welding technique ranges from 22 - 40 volts.